Heating appliance for canned food.



No. 654,!74. Patented July 24, I900.

E. MURMANN & A. UPAWSKI.

HEATING APPLIANCE FOR CANNED FOOD.

(Application filed Jam. 5, 1899.)

(No Model.)

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Y i50 I NETED STATES PATE T BFIGEs HEATING APPLIANCE FOR CANNED FO OD.

SPECIFICATION forming part of Letters Patent No. 654,174, dated July 24, 1900. Application filed January 5,1899. Serial No. 101,287. (No model.)

To all whom it may concern.-

Be it known that we, ERNST MURMANN and AUGUST OPAWSKI, subjects of the Emperor of Austria-Hungary, residing at Vienna, in the Province of Lower Austria and Empire of Austria-Hungary, have invented a new and useful Improvement in Heating Appliances for Canned Food, of which the following is a specification.

This invention relates to sealed sheet iron cans containing preserved food of such a nature as to require heating before being eaten. Hitherto it was necessary for heating such preserved foods to provide hot water or a wood or spirit fire. Now, our invention has for its object to obviate this necessity.

According to the invention a two-chambered sheet-iron receptacle is so connected with the can that the sides of the said receptacle are either in contact with the contents of the can or are partly formed by the sides of the saidcan. The two chambers of the receptacle, separated from each other by a partition, are filled with two different substances having chemical affinity-with one another and one of them being in a liquid state, whereby on the partition between the two chambers being pierced chemical reaction takes place and heat is developed. If one of the two substances referred to be water, which may be found nearly everywhere in nature, the said receptacle may have but one chamber. In this case the outer side of the receptacle is pierced when the food is required for use and water is introduced therein.

In the case of two-chambered receptacles one of the chambers may contain'a permanent device for piercing the partition between the two chambers or for loosening a solderedin partition, the said device consisting of a pin so held in position in the chamber that it pierces or loosens the partition when a portion of the receptacle is knocked in.

On slaking freshly-burned quicklime thirteen thousand sirt hundred calories of heat are evolved per molecule of hydrate formed. For this reason it has been repeatedly'proposed and tried to utilize this process for the purpose in question. However, the reaction between quicklime and ordinary water goes on comparatively slowly, and it is yet more retarded if alcohol or glycerin have been added to the water in order to prevent it from freezing fast. Most sensibly the reaction is delayed by keeping the quicklime, afteritsburnin'g, some time, of course at exclusion of air. In this case a quarter of an hour may often elapse before the evolution of heat begins, and the same is but weak. Especially with quicklime in small pieces and in contact with a good conductor of heat it is scarcely perceptible.

According to our invention we also utilize the reaction between quicklime and Water; but we accelerate the same essentially and in any required measure by causing not only water,but also a water-transferrer, to act upon the quicklime. There are,indeed, numerous salts and acids having the property that on their being dissolved in water they immediately combine with some molecules of water, but in so loose a manner that these molecules of water are more readily yielded to other compounds than molecules of the groups of molecules forming the water. As soon .as the water taken up by the salts and acids in question has been yielded to the other compound present the said salts or acids again combine with molecules of water severed from the surrounding water, and so on. It will thus be seen that the salts and acids referred to, so to speak, take the molecules of water from the water in presence and transfer them to the other compound.

As between the agents for transferring water, calcium chlorid is most effective. Next to it come calcium bromid and iudid,to which follow, with gradually-decreasing effectiveness, magnesium chlorid, bromid and iodid, ammonium chlorid, bromid'and iodid, zinc chlorid, bromid and iodid, and all soluble chlorids, bromids, and iodids of inorganic bases,- forinstance, ferrous oxidand organic onesfor instance, anilin, phenyl hydrazine-which can be decomposed by lime. There are only excepted the fixed alkalies, the chloride of which exert no action at all, while the effect produced by the bromide and iodide is but weak. Highly-diluted hydrochloric, hydrobromic, and hydroiodic acid give rise to the formation of the corresponding haloid com pounds of calcium, and consequently they act quite as accelerating as the calcium compounds themselves. In the second rank stand, as Weakly accelerating, the nitrates of cal with a given capacity thesaid receptacle excium, magnesium, potassium, sodium, and baryum, highly-diluted nitric and sulfuric acid, magnesium sulfate, ammonium molybdate, &c. No accelerating action or even a strongly-retarding action is exerted by alkali sulfates, alkali fiuorids, nitrites, alkali carbonates, alkali lyes, sodium tungstate, &c.

The action of calcium chlorid is so energetic that, for instance, quicklime, which but weakly enters into reaction with distilled or well water and not before about ten minutes, causes in a few seconds steam to be evolved if brought together with an aqueous solution of calcium chlorid at one-half percent. When the quicklime in question is thrown into an aqueous solution of calcium chlorid at but threeper cent, the evolution of heat takes place explosion-like.

In order to make our invention fully understood, we shall hereinafter describe'it in detail, with reference to the accompanying sheet of drawings, in which Figure. 1 is a sectional elevation of a can provided with our heating appliance; and Fig. 2, in its left-hand half a top View of the said can and in its right-hand half a sectional view on line 2 2, Fig. 1.

Referring to the drawings, 0 is a cylindric sheet-iron receptacle having a bottom 0 and being, by means of its top flangec soldered into a hole of the cover a of the can b. The diameter of the receptacles is so chosen that tends nearly to the bottom a of the can b.

The receptacle 0 is destined to receive quicklime or a mixture of the same with a watertransferrer. Into the open top end of the receptacle; cis soldered another receptacle f of similar form, but of smaller dimensions, and provided with a flange f, superposed upon the. flange c The receptacle f is filled' with water or with an aqueous solution of a water-transferrer. Atits top the receptacle f is closed by a solderedcover h,- convex to the outside, and thelreceptacle contains the pin: j, destined to pierce the partition between both chambers referred to above, this partitiom being formed bythebottom f of the receptacle f.

projects through a hole f of thebottom f and carries below the bottom a head j, which is. so; soldered to the said bottom as to close the hole f By flattening down the convex It will be seen that the pin j cover h by a blow with a heavy body the head j of the pin j is severed from the bottom f and the liquid is allowed to pass into the receptacle 0. It is obvious that the said pin j may also be dispensed with, as the liquid contained in the receptacle f may also be given access to the quicklime and watertransferrer or mere quicklime filling the receptacle c by piercing from without with'any suitable implement, such as a nail, both the cover h and bottom f We prefer, however, to use the described pin for piercing the partition without breaking the cover, as in this way the steam evolved is utilized for heating, while it otherwise escapes through the pierced cover.

If the: loss of heat inrthe form of escaping steam be not a sensible drawback, as will be the case when moreorless weight of, the. cans is not cared for, and consequently a comparatively-great quantity of quicklime may be used, and the heating appliance may be formed of a unique chamber containing quicklime and a water-transferrer.

What we claim as our invention ,and desire to secure by Letters Patent, is--- In a heating appliancefor canned food, the combination with the can of a sheet-metal reiceptacle tightly inserted into: a hole of the sides of the canand extendingwithin the hollow of the can nearly to the opposite: side, a cross-partition dividiengthe hollow space of the receptacle intoan intestine an. outer chamberand being providdfl'wlitlra hole-,.a headed pin having its head so soldered to the inner surface of the partition that it closes the hole of the partition, and its stem extending; into, the outer chambeiga bellied-out: sheet-metal cover tightly closing the, outer chamber and bearing against the tree end of the pin, quicklime filling either chambenwater filling the other chamber, and a watertransferrer added to the contents of. either chamber, substantially asvdescrihed and for the purposes set forth. a v

In witness. whereof? we have signed this specification in presence of two witnesses;

ERNST MURMANN'. AUGUST OPAWSKI.

Witnesses:

VICTOR VERPT, ALvEsro S. Hoops. 

